Deactivate any external data disk device on first boot (#2390) (#2410)

* Deactivate any external data disk device on first boot (#2390)

* Use lsblk to determine the underlying device file

Comparing major number is not reliable, e.g. virtio disks have the same
major number despite being different devices. Use lsblk to find the
underlying device, and compare the device name instead.

buildroot-external/rootfs-overlay/usr/lib/systemd/system/haos-data-disk-detach.service

@@ -0,0 +1,16 @@
+[Unit]
+Description=HAOS data disk detach
+DefaultDependencies=no
+Before=mnt-data.mount
+RefuseManualStart=true
+RefuseManualStop=true
+Requires=dev-disk-by\x2dlabel-hassos\x2ddata.device
+After=dev-disk-by\x2dlabel-hassos\x2ddata.device systemd-fsck@dev-disk-by\x2dlabel-hassos\x2ddata.service
+ConditionFirstBoot=yes
+
+[Service]
+Type=oneshot
+ExecStart=/usr/libexec/haos-data-disk-detach
+
+[Install]
+WantedBy=local-fs.target

buildroot-external/rootfs-overlay/usr/libexec/haos-data-disk-detach

@@ -0,0 +1,23 @@
+#!/bin/sh
+
+# Find root using rdev command
+rootpart=$(rdev | cut -f 1 -d ' ')
+rootdev=$(lsblk -no pkname "${rootpart}")
+
+# Wait up to 10s for devices to enumerate
+sleep 10s
+
+datapartitions=$(blkid --match-token LABEL="hassos-data" --output device)
+
+for datapart in ${datapartitions}
+do
+	datadev=$(lsblk -no pkname "${datapart}")
+
+	# If major does not match our root device major, it is an external data
+	# disk. Rename to make sure it gets ignored.
+	if [ "$rootdev" != "$datadev" ]
+	then
+		echo "Found external data disk device on ${datapart}, mark it disabled..."
+		e2label "${datapart}" hassos-data-dis
+	fi
+done